none The cocoons of three species of parasitic wasps belonging to Brachonidae, Apanteles glomeratus (host species; Pieris rapae), A. dictyoplocae (host species; Caligula boisduvalii), and Glyptapanteles pallipes (host species; Acanthoplusia agnata), were examined biochemically. Glue protein (wasp sericin) was separated with aqueous 8M urea from fibrous protein (wasp fibroin). The amino acid composition of the wasp sericin gave a similar profile to that of Bombyx mori sericin, but the wasp fibroin revealed an unique amino acid composition which consists of mainly serine and aspartic acid (containing asparagine) in contrast to that of B. mori fibroin Ecology; Animal constructions Apanteles dictyoplocae; Apanteles glomeratus; Glyptapanteles pallipes (Braconidae ); Cocoons; Characterization of silk proteins